A stroke is the disturbance in blood supply to the brain. Two major categories of strokes are ischemic strokes and hemorrhagic strokes. Ischemic strokes are caused when blood supply to part of the brain is decreased, thereby depriving the brain of oxygen and destroying brain tissue. Ischemic strokes may be caused by thrombosis (obstruction of a blood vessel by a blood clot forming in the blood vessel), embolism (obstruction of a blood vessel by an embolus traveling from elsewhere in the body, also known as an “embolic stroke”), systematic hypoperfusion (general decrease in blood supply, e.g., due to shock), venous thrombosis (obstruction of a blood vessel in the sinuses which drains blood from the brain). Hemorrhagic strokes are caused by a ruptured artery in the brain, which causes blood to pool and destroy brain tissue. Both ischemic and hemorrhagic strokes may cause severe deficits in a patient, therefore a patient that has experienced a stroke should seek medical treatment as soon as possible. Other medical conditions, such as atrial fibrillation, may cause a patient to be particularly susceptible to certain stroke types, such as embolic strokes.
Due to the different etiologies of ischemic and hemorrhagic strokes, each stroke type requires different treatment plans. For example, strokes caused by clotting (e.g., thrombolytic and embolic strokes) may be treated with a “clot busting” medication that should be administered within the first three hours of the onset of a stroke. When a stroke is properly treated, a patient's mental and physical deficits may be minimized. Misguided treatment plan (e.g., upon misdiagnosing a stroke) could progress the stroke and possibly lead to death.